1. Field of the Invention
The invention relates to a sensor apparatus for detecting a concentration of at least one gas component and a particle concentration of an exhaust gas. The sensor apparatus has a sensor carrier having a solid electrolyte.
2. Prior Art
Increasingly stringent statutory regulations require a reduction in the combustion exhaust gases emitted by a motor vehicle. In this connection, motor vehicles are increasingly being equipped with exhaust gas cleaning systems. A large number of sensors is required in order to monitor and/or control an exhaust gas cleaning apparatus of this kind.
DE 10 2006 048 354 A1 discloses a sensor element for identifying constituent parts of a gas mixture, in particular of an exhaust gas from internal combustion engines. The sensor element comprises a plurality of oxygen-ion-conducting solid electrolyte layers. Furthermore, the sensor element has a large number of electrically insulating ceramic layers. The sensor element furthermore has a ceramic heating element which is designed in the form of an electrical resistance conductor track and serves to heat up the sensor element, in particular to the temperature of the gas mixture which is to be determined, and/or to burn off the soot particles which have accumulated on large areas of the sensor element. Two measurement electrodes are fitted to a large area of the sensor element, said measurement electrodes preferably being in the form of interlocking interdigital electrodes. A reference gas channel which is preferably in contact with a reference gas atmosphere, such as air or oxygen for example, is arranged in one of the solid electrolyte layers. A reference electrode is arranged in the reference gas channel.
DE 103 22 427 A1 discloses a sensor for detecting particles in a gas stream, in particular soot particles in an exhaust gas stream, having measurement electrodes which are arranged on a substrate which is composed of an insulating material. The substrate comprises a solid electrolyte in which at least two oxygen pump cells, which each have an associated pair of electrodes, are formed. A diffusion barrier is connected upstream of at least one of the oxygen pump cells, said diffusion barrier having two further associated electrodes to which a high voltage can be applied.
DE 10 2005 049 775 A1 discloses a sensor for measuring the concentration of a gas component in a gas mixture. The sensor comprises an ion-conducting solid electrolyte. The sensor further comprises electrodes which are separated from one another by the solid electrolyte. From amongst the electrodes, an outer electrode is exposed to the gas mixture and an inner electrode is arranged in a cavity which is separated from the gas mixture by a diffusion barrier. The outer electrode consists of a solid body which leads to the formation of mixed potentials.